The invention is directed to an arrangement for the automatic and correct positioning with respect to time of a record chart bundle serving to record in segments but in a continuous manner relative to the recording members of a recording device. The record chart bundle being driven synchronously with respect to time by a recording gear mechanism or running gear and the drive connection of the individual record charts of the record chart bundle, which are provided in each instance with a sector-shaped cut-out portion and are arranged so as to be staggered relative to one another, is gradually interrupted.
As is known, record chart bundles are used in an advantageous manner when a process, which is of interest in its context, is to be detected over a longer range of time or when a better resolution of the recordings is to be achieved within a determined recording time range than would be possible with a single record chart which is relatively limited in its recording capacity. A preferred example of the use of such record chart bundles is in tachographs whose operation is substantially simplified by means of inserting record chart bundles which allow e.g. a weekly recording.
The continuous recording over a longer period of time, which is the aim of the record chart bundle, is achieved in that the recording members slide down to the next record chart in the bundle after practically one revolution as a result of the sector-shaped cut-out portions of a record chart. Accordingly, continued recording is effected, without a gap in time, on a new blank record chart, while the inscribed record chart, which is connected with the last record chart in the recording sequence or with a blind plate or blank flange, e.g. by means of a paper strip, is severed in the course of the continued movement of the record chart bundle by means of a suitable severing device with respect to the technique by which the record chart bundle is connected, e.g. a knife, which likewise falls into the cut-out portion of the inscribed record chart and is then actuated between the inscribed record chart and the following record chart. As the process proceeds, the friction of the severed record chart with the remainder of the bundle, which continues to rotate, and with its bush which is securely connected with the blind plate, guides the severed record chart against a stationary stop.
If the recordings are to be effected in a synchronous manner with respect to time and for later evaluation, particularly visually, with a time reference, it is necessary in the event that the bundled record charts are provided with the same time scales, that is, when they are not also recorded or printed on during the recording, not only to drive the respective record chart bundle in a manner corresponding to the time scale, but also to position them correctly with respect to time in the recording device, i.e. it is necessary that the scale value corresponding e.g. to the current clock time be aligned with the record chart located on top of the record chart bundle on the recording line, that is, the line that the recording members record on when they are moved out.
In previously used recording devices in which record chart bundles are used as recording charts, the recording base and the recording means are freely accessible. A record chart bundle is placed on by hand by threading its bush on a centering pin constructed at the recording means, which are driven by the recording gear mechanism in a synchronous manner with respect to time, and is secured by means of a tensioning nut, after which it is correctly aligned with respect to time to the recording line or to a permanent marking on the device which is assigned to the recording line, respectively, by means of rotating the record chart bundle. Of course, such an alignment of the record chart bundle depends to a great extent on the personal conscientiousness of the user and is cumbersome and subject to error by necessity if it must be carried out under the work conditions prevailing in the driver's cab of a truck, for example.
In order to change this situation in a fundamental way, i.e. to facilitate handling and increase the accuracy of positioning the record chart bundle, and accordingly also to improve the acceptability of such a recording device, it is obvious to demand a recording device in which the record chart bundle is inserted into a pocket and the rest of the operation is effected automatically. A threading of the record chart bundle on a centering spike with an eccentric projection, as is customary in the receiving of individual record charts, is already ruled out because of the cylindrical bush of the record chart bundle, but also because the time scales of the record charts of the record chart bundle are offset relative to one another and the rate of rotation of the record chart bundle, i.e. the recording speed, is lower than a speed which is identical to the actual recording duration per record chart. However, it is conceivable that a marking be assigned to a determined scale value on every record chart of a record chart bundle, and that by setting the record chart bundle in rotation the record chart bundle is guided back by a corresponding time difference between the scale value of the marking and the current clock time when the marking is detected by means of a stationary sensor in such a way that the scale value corresponding to the current clock time coincides with the recording line. Such a solution is inappropriately costly on the one hand with respect to the required drive means and the electronic comparison device; and on the other hand, difficulties arise with respect to a slip-free carrying of the record chart bundle during the positioning movement because of the cylindrical bush of the record chart bundle.